I agree. I have 7:44 in my training diary for a BFT in Feb 1984 in Muelheim. I'd be surprised if I did that in boots and denims, though I suppose it is possible as a racing snake.Much later, I didn't join until 1983. And from my recollection, must people significantly reduced their time.
That's the problem with reminiscing, everyone remembers differently
As a comparator my 5000m on a tartan track in needle spikes that year was 16:08.